FLOOD03246

• County: Statewide
• Community: Nationwide
• Basin: Statewide
• Title: Pollution Characteristics of Stormwater Runoff Completion Report
• Date: 9/1/1978
• Prepared By: CSU Environmental Resources Center
• Floodplain - Doc Type: Educational/Technical/Reference Information

This was compared with observations of the lead content in snow,

water, and ice sampled on road surfaces and adjacent areas.

Concentrations of lead from road edges averaged 5.5 mg/l, ranging

from 3.6 to 8.5 mg/l. Again, concentrations of lead in samples

taken at points away from the roadbed decreased with increasing

distance from the roadbed. A value of 0.09 mg/l was reported

for lead concentrations in a sample obtained from an "open field

surrounded on three sides by heavily traveled streets". Observa-

tions were compared with the theoretical value and a number of

factors were suggested to explain the differences.

Bryan (1970) in his original Durham, N.C. study on urban

runoff, noticed erratic BOD results. Exploratory work indicated

"evidence of toxicity to the reaction (BOD) detected in some

samples which upon further exploraticn revealed presence of lead

at concentration levels in the order of 1.0 mg/l." A subsequent

study on the same drainage area revealed lead concentrations in

the storm water runoff to range from 0.10 mg/l to a maximum value

of 12.6 mg/l. The yield of lead from the predominantly residential

area within the drainage basin was one-half of that from the more

commercially developed area, and was almost exactly in proportion

to the percentage of paved surfaces (Bryan, 1972). In addition,

the yield of lead presumed to originate from "internal combustion

engines operating on and near the basin was determined to be

0.0006 Ib/day/acre (0.00067 kg/hectare/day)."

C. Effects of Storm Pattern
Several researchers have investigated the relationship of
duration and intensity of a storm with the resulting runoff

23

~